Write error response schema for APIs

[abskrj]

We need to write an Error response schema to be returned from API. Like this

{
    "error": "Error parsing JSON request",
    "message": "Invalid JSON format",
    "detail": "Post the 'author' and 'id' fields in the request body."
    "statusCode": 400
}

[scoobhidu]

I would like to pick this up @abhishekraj272

[abskrj]

ignore the above message ^^

[scoobhidu]

@abhishekraj272 shouldn't the status code be set in the API response only instead of sending in body?

[abskrj]

check this out: https://softwareengineering.stackexchange.com/questions/305250/should-i-use-http-status-codes-to-describe-application-level-events

[uzaxirr]

A map should be added in constants/constants.go

const HTTPStatusCodes := map[int]string{
	http.StatusOK:                   http.StatusText(http.StatusOK),
	http.StatusCreated:              http.StatusText(http.StatusCreated),
	http.StatusAccepted:             http.StatusText(http.StatusAccepted),
	http.StatusNonAuthoritativeInfo: http.StatusText(http.StatusNonAuthoritativeInfo),
	http.StatusNoContent:            http.StatusText(http.StatusNoContent),
	http.StatusBadRequest:           http.StatusText(http.StatusBadRequest),
	http.StatusUnauthorized:         http.StatusText(http.StatusUnauthorized),
	http.StatusForbidden:            http.StatusText(http.StatusForbidden),
	http.StatusNotFound:             http.StatusText(http.StatusNotFound),
	http.StatusMethodNotAllowed:     http.StatusText(http.StatusMethodNotAllowed),
	http.StatusConflict:             http.StatusText(http.StatusConflict),
	http.StatusInternalServerError:  http.StatusText(http.StatusInternalServerError),
}

Create a new directory and file types/types.go this file will contain the struct which can be used for both Error and Sucess Response

types/types.go

type Response struct {
	Status  int         `json:"status"`
	Data    interface{} `json:"data"`
	Error   interface{} `json:"error"`
}

and then you can modify the controller, an example of what the Ping controller may look like is

func Ping(c *gin.Context) {
	response := Response{
		Status: HTTPStatusCodes[http.StatusOK],
		Data:   "pong",
		Error:  struct{}{},
	}
	c.JSON(http.StatusOK, response)
}

It may give the below output

{
    "status": 200,
    "data": "pong",
    "error": {}
}

And for the /generate-presigned-url

response := Response{
	Status: HTTPStatusCodes[http.StatusOK],
	Data: map[string]interface{}{
		"preSignedURL": "https://somebucket-bucket.s3.amazonaws.com/abcdefg",
		"videoID":      "109934677.mp4",
	},
	Error: struct{}{},
}

and in case of error the Data feild will be empty while the Error field will have the appropriate info